Individual selective lock-out device for party-line telephone systems.



W. M. BRUCE, JR. LooKoUT DEVICE FoP. PARTY LINE TELEPHONE SYSTEMS. APPLIGATON FILED SEPT.1,1904.

INDIVIDUAL SDLBDTIVD Patented June 6, 1911.

3 SHEETS-'SHEET 1.

[Juvcul'or ChloznuJJ W. M. BRUCE, JR. INDIVIDUAL SELBCTIVE LOCKOUT DEVICE FOR PARTY LINE TELEPHONE SYSTEMS.

APPLICATION FILED SEPT.1,1904.

Patented June 6, 1911 3 BEBETSdSEEET 2.

V uuculor W. M. BRUCE, JR. LOGKOUT'DEVIGE POE PARTY LINE APPLIo'ATIoN FILED SEPT. I, 1904.

TELEPHONE SYSTEMS.

INDIVIDUAL SBLBGTIVI:

Patented June 6, 1911.

3 SHEETS-SHEET 3.

" I Abi fully described. When the step-up rod is moved, however, in the act of calling a subscriber, the cam-roller leaves the cam-shaped portion of the rod, and allows the circuit hrcaker to open, thus breaking the sul scribcrs circuit as soon as a call is started, which circuit, in each instrument remains broken until the instrument returns to zero, thus eticctually locking out all subscribers exceptingv the one to be selected, in the manner hereinafter more fully described.

, The preferable form of4 circuit breaker above described is shown in Figs. 4 and 8. lin Figs. l, 2 and 3 a slightly different :t'orin is shown, a cam-projection on the step-up rod being,r adapted to engage a camesurface on the switch for opcninggr and closing the `same by the movement ot' said rod.

For indicating to each subscriber when the line is in use,1 employ an indicator, a3", adapted to bc operated by the step-up rod when it reach a its calling position, that is to say, the next to the last step, this indicator being adapted to show the word busy, or some similar sign, through a suit:- able opening,r in the ini-,losing casing, to in* dicatc that tzhc line. ia in use. In Fig. 5, `I have shown this busy sign pivotcd ad jacent to thc rod, and having' a projection which rmrmally engages in a notch, u2, on said rod, in which position it will drop away from the opening as the. rod is moved, however, the notch being cainohaped, raises the aigu into its indicatingposition. In Fig. t), l have shown a moditication in the busy sign being attached directly to the end of the rod, and when the rofl rcacl'iel its callingr position, or the next. to last step, the sign will be brought opposite 'the openinpr in the casing. Various forms o t' indicator conncctioi-is may be used for this purpose.

The circuits and connections it'or the dit* 'ferent will, probably, be best under` stood t'roin the diagrammatic View, Fig. il,

where the main telephone liuc is yshown at. t and c. The step-up magnet, u, is bridged acrosay this line, as ilnlicated by the circuit connection c and "2 in addition to the .itepaip arn'laturc, the .step-up magnet is provided with an auxiliary armature, uit, which may be arranged at the opposite end thereof, and .vhiich in adapted to operate a circuit. breaker, in the subscribcfs talking circuit, when the stcpalp magnet is energized, tor the ignirpofax hereinafter more fully Set itorth. ',ihc eubscribcfs talking outlit, is also norrnz'illy bridged across the line by branch circuits extending from the circuits, ci? and cf, and paesino; through the circuit breL ker operated by the armature, (52" and thc circuit breaker, el", oiicrated by the cam, c, tiiroufrli the receiver, c in the usual w y. no that'when the receiver, el refoto the loeches, and the'local batw tery circuit, f, being;r closed at c in the sub scribers instrument the subscriber can talk direct to the central .station with the instruments in their normal position, any Suitable calling device, such as g1, being,r employed for signaling the central station. The selector magnet, e, however, is located in a grouinled circuit from one side, d, of the main line only, which circuit can be traced from ground at c?, through the hook, c, line, e", Selector teiniinal, at", rod, a, line e", line cw, selector magnet, c, line, e to d. The receiver or talking circuit is also branched from the switch, c, through line, c, and switch, o, and line el, so that when thc circuit breaker, el, is open, the receiver or talking circuit is opened until closed by the switch, L, at the operation ot' the se lector armature, u.

At the central station l employ a movable contact device having as many contacts as there are subscribers on the line, and this contact device is placcd in circuit with the ordinary ringing generator, g, at the ccnl trai station. l. have shown a rotary device which may bc adapted to be rotated in any Suitable manner by clock work, or otherwise, and started and stoiipcd in any well known manner. This rotating contact device has contacting projections, ol, which as the device rotates, co1 i successively in contact `with a .spring o, so that at cach successive contact an impulse is scnt'ithrough the main line and through cach of the step up magnets, thus raising cach step-up rod one step :t'or each contact.

In addition to the movable contacts, o1, there a'rc a series ot contact points, o, one for each subscriber, and so 'tormed in connection with the callingr device that the operator by the employment of iilugs' or switches may select one contact point with which a` movable contacting arm, 7), will 'l'ornt an electrical coniicction during the movement ol the exchange device. ln the construction shown, a spring' arm, bt, rolater with the disk which carries the movable contacting,r parts, and'during its revolution it is adapted to contact with one of the contacting points, o, simultaneously with the connection between one ol the movable points, b1 yand the spring h2. The contact point, o, intimated, while the arm, is connected through the generator to that yside` f/ ot' thc main line I'rom which the brauch circuit leads to the lselector magnet, therefore when a contact is made bctwccn the arm, o, and the I'u'oicction, o, the Sclector magnet .in that .station whose se lector terminal corresponds to the `step op posite to which thc projection. o, is placed, will bc operated, closingI the switches, ff" and o, which switches' will be locked in this position by the armature lock', om. 'lhe step-up device, however, will continue `in Slt) Iitltl each of the instruments until they are stepped up to the-next .to ,the last step, only one instrument, however, will rbe selected as all the selector circuits Will belopened when the impulse passes from ground through the Contact, b3, except that one 'one whose terminal selector is on the ringe, and inasmuch as all the talkingI circuits at the switch, @15, on the irst movement of the stepup rod, all subscribers will he locked out except the magnet has been operated.

Thestep-up device in the subscribers station having been operated, the one selected may be called by the central otiice by the switch, et, which is placed in the grounded connection With thc'generator, g, the circuit being traced at the ground trom the central station through the generator, main line, d, selector magnet, line e, subscriberis bell, `switch Z123, line en, line c", and to round at c7 this connection beine broken,y

when the subscriber removes his telephone from the hook to establish the local' battery through switch c, battery, f, and transmitter in the usual Way,`

F or releasing the line and returning all the instruments to normal position, means are provided for giving each of the step-up devices an additional step,'and this a@ complished by sending an additional impulse through the step-up magnet. This may be accomplished by a separate switch, as shown at b5, adapted to close circuit from the generator' through the main line and the step-up magnet, as before described. rlhis switch may be a part, of the Vregular step-up mechanism adapted to beclosed by the operation which releases the line, or vit may be manually operated to give an additional impulse after the regular calling` device has made its complete circuit. vin any event, the additional impulse passing through the step-up magnet will produce an additional step inthe rod which will operate the rod, a1", and disengage the oper ating` and holding pavvls ior` the step-up rod and the catch for the selector armature, in the manner heretofore described, permitting all the parts'to return to their normal position.

When the s ubscribcrdias been selected by the operation of the selective mechanism, his receiver is bridged across the main line and in position for communication With central or other subscribers to Whom he may be connected.V Twopaths are open for the current, and as that of the receiver circuit may be of less resistance than that ot the step-up magnet, sulicient current might not he secured through the step-up magnet to produce the necessary movement of said magnet to release the line. To obviate any difhculty'of this kind, the circuit breaker operated by the arma-ture, f1.2", on the step- I energy in the step-up magnet,

are broken one Whose selector.

` the alternations or entrava up is introduced into the receiver circuit, as shown in Fig. 4;, and as hereton fore referred to. This armature will be operated by a very slight amount of electric and suti'lcient current will always pass through the stepup :magnet to operate said armature, although it might not be of suficient strength to operate the step-up armature and the stepnprod. The rst electrical impulse passinor through the step-up magnet will op erate tie anni iary armature, and thus break the receiver circuit; the receiver circuit being broken the only path ior the current is through the step-up magnet which thus gets the entire amount of current passing romthe central. station, and operates the stepup armature with suftiriientl force to move the stepuip device, and releases the line, thus making it possible to release the line under any conditions and against the will ot' the subscriber, it such becomes necessary.

.it Will be seen by the above construction l produce a selective loclreout system which. is' capable oi operation from the censtation, electrical in its operation and capable of operation under various indueuces and conditions which apply to telephone exchanges.

Will be understood that ordinarily an ernating current could not be satisfactoriiy used to operate a step-up device, since the current would be of toogreat 'frequency to be depended on for that purpose, but by having means tor controlline the operating pawl and holding it against the induence of the alternating current until such current is broken, l amenabled touse the alternating current in such a manner that the pavvl can onlyoperate thefsteA -up rod one tent o movement of the operating pawl While the step-up'magnct is under the intluenoe of the alternating current being positively controlled. 4

i7 hide l have described thisv device as especially adapted to the use oi the alternating' current for operating the step-up device. it is obvious that its use is not confined to an alternating current as it is equally adapted to the use of a direct current.

Having thus described my invention, I claim c y l. ln selective device for telephone systems, a step-up contactingdevice consistingr of a cylindrical supporting rod having a series ot circumferential notches and-a circular or circumferential contacting element, a step-np magnet and a reciprocatinp, pavvl oper-ated by the magnet to engage in said notches to move the rod upwardly, acircuitj closer adjacent to andadapted to contact with the contactingr element on the said rfid in combination with aselector magnet inr circuit with said circuit closer, a holding step at a time, the er ioo rosv` pawl for said rod,and means for disengaging said pawl to permit said rod to return byV gravity to its normal position.

2. .ln a selective system, a main telephone line, a step-up magnet bridged across said line, and a Vtelephone outlit and a circuit breaker through which said telephone outlit is normally closed to said line, a vertically moving cylindrical step-up rod operated by said step'up magnet to eontrol'said circuit breaker and open said subscribers circuit, said rod being supported in bearings so as to be free to turn as Well as to move longitudinally, a selector magnet in a norma ly open circuit and an adjustable circuit closer adjacent to said rod and a circular contacting element on said rod adapted to engage said circuit closer and close the circuit through said selector magnet and means connected with the selector magnet tor closing said telephone circuit.

3. In a selective instrument for party line telephones, a vertical moving cylindrical step-up rod having circumferential notches, a step-up magnet and paWl pivoted to the armature of said magnet to engage said notches, a telephone circuit normally closed to line by means controlled by said rod, a selector magnet and a circuit therefor including an adjustable circuit closer, and circular contact element on said step-up rod to engage said circuit closer to close the circuit of said selector magnet and means for successively energizing said step-up magnet.

la .ln a selective instrument 'for telephones, a vertically moving stepup rod having a series of circumtercntial notches a magnet `whose armature is adapted to move said rod at each impulse in said magnet, means 't'or holding said rod against return movement, and a releasingl device adapted to be operated by a separate impulse to permit it to return to its normal position by gravity, a circumferential contact on said rod and an auxiliary circuit adapted to be closed thereby at a predetermined movement ot' said rod said rod being supported in bearings which permit of a rotary as well as longitudinal movements whereby it is 'free to move and to ctl'ect its Contact operation in any position of rotary adjustment.

5. ln a selective instrument, the combination with a vertically moving step-up rody having a series of notches, a magnet adjacent to said rod, a reciprocating pawl moved by said magnet to engage said notches and impart a step-by-step movement to said rod, a holding pawl for said-rod, a

subscriber-s talking circuit closed by means operated by said rod which is adapted to be broken by the lirst movement thereof, a selective device adapted by a predetermined movement of said rod to reestablish said talking circuit, a busy signal operated by said rod When said rod has reached the normal limit ot' its upward movement, and means independent or' said magnet for releasing each ol said pawls to permit said rod to drop by gravity to reestablish said talking circuit and cancel said busy signal.

6. ln a selective instrument for telephones, a vertically moving step-up rod having a series ol notches, a step-up magnet.

adapted to Operate said rod, and a subseribers telephone outfit normally closed to line by a circuit breaker operated by the first movement of said step-up rod, a selector magnet adapted to be brought into circuit by a predetermined movement of said rod, and means connected to said selector magnet for closing said telephone circuit when the same is operated, and a circuit breaker operated by said step-up magnet also adapted to break said telephone circuit when said magnet is operated, substantially as specified.

7. In a selective telephone system, the combination of a source of alternating current, a'main line, a magnet bridged across said main line, a step-up device operated by said magnet, means for controlling the extent of movement of said step-up device while under the influence of said magnet, a receiver circuit normally bridged across said main line, and means for automatically opening said receiver circuit to increase the flow of current through said magnet, substantially as specified.

8.111 a selective telephone system, the minnbination of a main line, a magnet permanently bridged across said line, a step-up device operated by said magnet, a` receiver circuit adapted to be bridged across said main line upon a predetermined movement of said stcp-up device, and means controlled by said stcp-up device for automatically breaking the receiver' circuit at each electrical impulse through said magnet, substantially as specified.

In testimony whereof, l have hereunto set my hand this 17th day ot August A. D. 1904.

V/ILLIAM M. BRUCE, J'n.

"Witnesses Guns. I. Wenen, CLIFTON I. GRANT. 

